When two microphones are used in stereo operation, interference effects (stereo noise) can occur if the two microphones are connected to a DSP via a single line. Charge reversal effects give rise to additional power loss that causes interference (stereo noise) in the audio band by way of the thermo-acoustic effect. The stereo noise causes a deterioration in performance, such as e.g. a reduction of the SNR (SNR=signal-to-noise ratio).